Damping of the Higgs and Nambu–Goldstone modes of superfluid Bose gases at finite temperatures
Damping of the Higgs and Nambu–Goldstone modes of superfluid Bose gases at finite temperatures
We study collective modes of superfluid Bose gases in optical lattices at commensurate fillings. We focus on the vicinity of the quantum phase transition to the Mott insulator, where there exists the Higgs amplitude mode in addition to the Nambu–Goldstone phase mode associated with the spontaneous U(1) symmetry breaking. We …